The present invention relates to a novel resin composition having excellent heat resistance and flame retardance without flame dripping during combustion.
Recently, the demand for ABS (acrylonitrile-butadiene-styrene) resins possessing both heat resistance and flame retardance without the flame dripping phenomenon during combustion has rapidly increased. Use of ABS resins has greatly increased, from application in all kinds of household electric appliances to high precision industries such as computer monitor housings.
A known method of imparting flame retardant characteristics to ABS resins involves incorporation of polyvinylchloride and/or flame retardants containing halides into ABS resins along with at least one or more inorganic compounds such as antimony trioxide. However, the physical properties of flame retardant ABS manufactured by the above method are decreased to an undesirable level, since the flame retardants must be used in large quantities to both prevent flame dripping and reduce the ignition time to a desirable extent. Moreover, because the prices of most flame retardants are much higher than that of ABS resin, the flame retardant ABS manufactured by above method is economically inefficient.
The present inventors have solved the above problems by incorporating flame retardants and thermoplastic phenoxy resin into ABS resin, which is described in Korean Patent Publication No. 86-974. This resin composition possesses well-balanced physical properties and flame retardance without flame dripping.
Nevertheless, recently flame retardant ABS resins with a higher heat deflection temperature have been required. In order to satisfy such needs, the present invention provides an improved heat deflection temperature compared with the previous flame retardant ABS resin composition without significant deterioration of flame retardance or other physical properties.